use crate::consts::{constant, Constant};
-use crate::rustc::hir::{Expr, ExprKind};
-use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use crate::rustc::{declare_tool_lint, lint_array};
-use crate::syntax::ast::LitKind;
-use crate::utils::{is_direct_expn_of, span_help_and_lint};
+use crate::utils::{is_direct_expn_of, is_expn_of, match_qpath, span_help_and_lint};
use if_chain::if_chain;
+use rustc::hir::*;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::{declare_lint_pass, declare_tool_lint};
+use syntax::ast::LitKind;
+use syntax::source_map::symbol::LocalInternedString;
-/// **What it does:** Check to call assert!(true/false)
-///
-/// **Why is this bad?** Will be optimized out by the compiler or should probably be replaced by a
-/// panic!() or unreachable!()
-///
-/// **Known problems:** None
-///
-/// **Example:**
-/// ```rust
-/// assert!(false)
-/// // or
-/// assert!(true)
-/// // or
-/// const B: bool = false;
-/// assert!(B)
-/// ```
declare_clippy_lint! {
+ /// **What it does:** Checks for `assert!(true)` and `assert!(false)` calls.
+ ///
+ /// **Why is this bad?** Will be optimized out by the compiler or should probably be replaced by a
+ /// panic!() or unreachable!()
+ ///
+ /// **Known problems:** None
+ ///
+ /// **Example:**
+ /// ```rust,ignore
+ /// assert!(false)
+ /// // or
+ /// assert!(true)
+ /// // or
+ /// const B: bool = false;
+ /// assert!(B)
+ /// ```
pub ASSERTIONS_ON_CONSTANTS,
style,
- "assert!(true/false) will be optimized out by the compiler/should probably be replaced by a panic!() or unreachable!()"
+ "`assert!(true)` / `assert!(false)` will be optimized out by the compiler, and should probably be replaced by a `panic!()` or `unreachable!()`"
}
-pub struct AssertionsOnConstants;
-
-impl LintPass for AssertionsOnConstants {
- fn get_lints(&self) -> LintArray {
- lint_array![ASSERTIONS_ON_CONSTANTS]
- }
-}
+declare_lint_pass!(AssertionsOnConstants => [ASSERTIONS_ON_CONSTANTS]);
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for AssertionsOnConstants {
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx Expr) {
- if_chain! {
- if is_direct_expn_of(e.span, "assert").is_some();
- if let ExprKind::Unary(_, ref lit) = e.node;
- then {
- if let ExprKind::Lit(ref inner) = lit.node {
- match inner.node {
- LitKind::Bool(true) => {
- span_help_and_lint(cx, ASSERTIONS_ON_CONSTANTS, e.span,
- "assert!(true) will be optimized out by the compiler",
- "remove it");
- },
- LitKind::Bool(false) => {
- span_help_and_lint(
- cx, ASSERTIONS_ON_CONSTANTS, e.span,
- "assert!(false) should probably be replaced",
- "use panic!() or unreachable!()");
- },
- _ => (),
- }
- } else if let Some(bool_const) = constant(cx, cx.tables, lit) {
- match bool_const.0 {
- Constant::Bool(true) => {
- span_help_and_lint(cx, ASSERTIONS_ON_CONSTANTS, e.span,
- "assert!(const: true) will be optimized out by the compiler",
- "remove it");
- },
- Constant::Bool(false) => {
- span_help_and_lint(cx, ASSERTIONS_ON_CONSTANTS, e.span,
- "assert!(const: false) should probably be replaced",
- "use panic!() or unreachable!()");
- },
- _ => (),
+ let lint_assert_cb = |is_debug_assert: bool| {
+ if let ExprKind::Unary(_, ref lit) = e.kind {
+ if let Some((Constant::Bool(is_true), _)) = constant(cx, cx.tables, lit) {
+ if is_true {
+ span_help_and_lint(
+ cx,
+ ASSERTIONS_ON_CONSTANTS,
+ e.span,
+ "`assert!(true)` will be optimized out by the compiler",
+ "remove it",
+ );
+ } else if !is_debug_assert {
+ span_help_and_lint(
+ cx,
+ ASSERTIONS_ON_CONSTANTS,
+ e.span,
+ "`assert!(false)` should probably be replaced",
+ "use `panic!()` or `unreachable!()`",
+ );
}
}
}
+ };
+ if let Some(debug_assert_span) = is_expn_of(e.span, "debug_assert") {
+ if debug_assert_span.from_expansion() {
+ return;
+ }
+ lint_assert_cb(true);
+ } else if let Some(assert_span) = is_direct_expn_of(e.span, "assert") {
+ if assert_span.from_expansion() {
+ return;
+ }
+ if let Some((panic_message, is_true)) = assert_with_message(&cx, e) {
+ if is_true {
+ span_help_and_lint(
+ cx,
+ ASSERTIONS_ON_CONSTANTS,
+ e.span,
+ "`assert!(true)` will be optimized out by the compiler",
+ "remove it",
+ );
+ } else if panic_message.starts_with("assertion failed: ") {
+ span_help_and_lint(
+ cx,
+ ASSERTIONS_ON_CONSTANTS,
+ e.span,
+ "`assert!(false)` should probably be replaced",
+ "use `panic!()` or `unreachable!()`",
+ );
+ } else {
+ span_help_and_lint(
+ cx,
+ ASSERTIONS_ON_CONSTANTS,
+ e.span,
+ &format!("`assert!(false, \"{}\")` should probably be replaced", panic_message,),
+ &format!(
+ "use `panic!(\"{}\")` or `unreachable!(\"{}\")`",
+ panic_message, panic_message,
+ ),
+ );
+ }
+ }
+ }
+ }
+}
+
+// fn get_assert_args(snip: String) -> Option<Vec<String>> {
+//
+// }
+
+fn assert_with_message<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) -> Option<(LocalInternedString, bool)> {
+ if_chain! {
+ if let ExprKind::Match(ref expr, ref arms, MatchSource::IfDesugar { contains_else_clause: false }) = expr.kind;
+ // match expr
+ if let ExprKind::DropTemps(ref expr) = expr.kind;
+ if let ExprKind::Unary(UnOp::UnNot, ref expr) = expr.kind;
+ //if let ExprKind::Lit(ref lit) = expr.kind;
+ if let Some((Constant::Bool(is_true), _)) = constant(cx, cx.tables, expr);
+ //if is_true;
+ // match arms
+ // arm 1 pattern
+ if let PatKind::Lit(ref lit_expr) = arms[0].pat.kind;
+ if let ExprKind::Lit(ref lit) = lit_expr.kind;
+ if let LitKind::Bool(true) = lit.node;
+ //if let LitKind::Bool(true) = lit1.node;
+ // arm 1 block
+ if let ExprKind::Block(ref block1, _) = arms[0].body.kind;
+ if let Some(trailing_expr1) = &block1.expr;
+ if block1.stmts.len() == 0;
+ //
+ if let ExprKind::Block(ref actual_block1, _) = trailing_expr1.kind;
+ if let Some(block1_expr) = &actual_block1.expr;
+ // function call
+ if let ExprKind::Call(ref func, ref args) = block1_expr.kind;
+ if let ExprKind::Path(ref path) = func.kind;
+ // ["{{root}}", "std", "rt", "begin_panic"] does not work
+ if match_qpath(path, &["$crate", "rt", "begin_panic"]);
+ // arguments
+ if args.len() == 2;
+ if let ExprKind::Lit(ref lit) = args[0].kind;
+ if let LitKind::Str(ref s, _) = lit.node;
+ let panic_message = s.as_str(); // bind the panic message
+ if let ExprKind::AddrOf(MutImmutable, ref inner) = args[1].kind;
+ if let ExprKind::Tup(ref elements) = inner.kind;
+ if elements.len() == 3;
+ if let ExprKind::Lit(ref lit1) = elements[0].kind;
+ if let LitKind::Str(ref s1, _) = lit1.node;
+ if let ExprKind::Lit(ref lit2) = elements[1].kind;
+ if let LitKind::Int(_, _) = lit2.node;
+ if let ExprKind::Lit(ref lit3) = elements[2].kind;
+ if let LitKind::Int(_, _) = lit3.node;
+ // arm 2 block
+ if let PatKind::Wild = arms[1].pat.kind;
+ if let ExprKind::Block(ref block2, _) = arms[1].body.kind;
+ if let None = &block2.expr;
+ if block2.stmts.len() == 0;
+ then {
+ return Some((panic_message, is_true));
}
}
+ return None;
}